Looping around database reader & Column filter


So I was wanting to create a workflow that takes a different csv each time, and the same table each time, filter some columns out, rename a couple of columns and then join them.

I'm fairly sure the csv loop works fine, but I can't work out how to get it to loop so it loads the same table from MySQL, and then filter different columns each loop.

I've left a .png showing what the workflow looks like.




Hi Daniel,

you need to connect the column filter into the loop. You can do this via the flow variable port.

Currently the column filter nost (22) is only executed once. Not with every iteration of the loop. Only nodes which are inbetween the loop start and the loop end node are part of the loop and will be executed with every iteration of the loop.


Did you already see our video series about loops? https://tech.knime.org/wiki/looping-in-knime 

Best wishes, Iris